The ultrasonic fluid measurement apparatus is an apparatus for allowing a fluid to flow into a measurement flow path, propagating an ultrasonic wave in the measurement flow path, measuring the propagation time of the ultrasonic wave, and finding the flow velocity of the fluid based on the measurement information.
The measurement flow path is provided with a pair of transducers on each of short side faces opposed to each other shaped in a rectangular cross-section pipe rectangular in cross section.
The pairs of transducers are placed so as to transmit and receive an ultrasonic wave along a line crossing at a predetermined angle relative to the flow direction of the measurement flow path.
In recent years, to enhance the measurement accuracy, an ultrasonic fluid measurement apparatus wherein a plurality of partition walls are placed in parallel in a measurement flow path for making the measurement flow path a multilayer flow path has been proposed (for example, refer to patent document 1).
Patent document 1: International Patent Laid-Open No. 04/074783 pamphlet